You beat me to it

but don't forget the android app version as well, from my kin web page:
android app:
from:
https://play.google.com/store/apps/deta ... calculatorhttp://download.cnet.com/GW2-Trade-Post ... 64365.htmlDescription
We've all been there. You see a seemingly good deal on the Trade Post, and you would like to make a quick buck from it. But, you do not know if you'd make money reselling your item or lose money in the process.
Not anymore.
With this simple but functional calculator you will instantly be able to tell weather you'll be climbing the ladder of Guild Wars 2 riches, or throwing money down the drain.
Simply put in your desired buying and selling price, as well as the amount of items you're planning to buy and you will instantly see your profit.
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Feel free to email me with suggestions for this app. Since this is only the first release, I'm sure there will be features you'd like to see added.
Special thanks to
http://namtar.com/gw2/tpcalc/ for giving me this idea.
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This app is not affiliated with or endorsed by game’s developer, publisher, or distributor. All imagery, and on the application are copyrighted by their respective owners. This calculator is for informational purposes and meant to assist fans of Guild Wars 2.
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web page version:
http://tpcalc.com/Guild Wars 2 trading post calculator.
Vendoring your items is more profitable at times.
www.guildwars2riches.com/2012/09/guildw ... lator.htmlThen a few make money guides:
making money
http://www.guildwars2guru.com/topic/614 ... ld-wars-2/With Both Feet: Trading Post Rage (Plus Profit Margins)
http://www.guildwars2guru.com/topic/614 ... ld-wars-2/ www.guildwars2riches.comWelcome to the Guild Wars 2 Spidy website!
This website aims to provide you with graphs of the sale and buy listings of items on the Guild Wars 2 Trade Market.
www.gw2spidy.comGuildwars Trade
www.guildwarstrade.comHow To Make Gold In Guild Wars 2
https://www.youtube.com/watch?v=wl3wZWnp-6wAND my don't forget the FEES post:
from:
http://wiki.guildwars2.com/wiki/Trading_PostPurchases on the trading post must be made using coin and there are two fees applied to sales: 5% of the asking price to list and a 10% tax on purchase.
Fee notes
The listing fee is shown before you press the submit button, but the sales tax is not shown (neither in the sales window nor in the pickup window).
Both fees are mathematically rounded, i.e. fractions less than one-half a coin are rounded down; fractions above that are rounded up.
Rounding examples
Selling one item for 29 Copper coin should generate a 1.45 Copper coin listing fee; you pay 1 Copper coin instead.
Selling another item for 31 Copper coin costs 2 Copper coin, i.e. rounded up from 1.55 Copper coin.
Losing potential earnings
Be careful not to list for so little that you would take home less than you would get by selling the item to a vendor, i.e. never sell for less than ~20% more than the item's value. For example:
An item of 88 Copper coin can be sold on the trading post for 89 Copper coin, but this results in 76 Copper coin (after deducting 9 Copper coin for a successful sale and 4 Copper coin for the listing fee).
If offered for 1 Silver coin 26 Copper coin, you would take home 1 Silver coin 7 Copper coin, 19 Copper coin more than the price the vendor offers (after paying a sales tax of 13 Copper coin, listing fee of 6 Copper coin)
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think you can fore go all this if you remember the rule of thumb that to make ANY money at the TP you need to multiply the vendor price by 20% to cover all fees